Rapid development of smart devices, for example, emergence of smart earphones, facilitates practice of applications having a healthcare function, for example, detection of heart rate, blood oxygen and the like biological features. Specifically, these smart devices are used in scenarios of monitoring the heart rate and blood oxygen during exercise or movement to judge whether the biological feature of a user is normal, or monitoring the heart rate and blood oxygen during sleeping to judge whether the biological feature of a user is normal.
With regard to the practice of the above applications having the healthcare function, the current commonly used manner is: measuring the biological feature based on optical theories, for example, the light reflection law and the light transmission law. Using the light reflection law as an example, the light emitted by a light emitter is incident to the biological tissue and then reflected by the biological tissue, and a light receiver receives the reflected light and performs biological feature detection based on the reflected light. During this process, the incident light is absorbed and diffused under effects of the blood in the tissue and then the reflected light to be transmitted to the reflector is formed. Since the blood in the tissue may be periodically changed, the reflected light may be also changed, and the biological feature may be obtained by sensing and analyzing the reflected light. Analogously, with respect to the light transmission theory, the biological feature may be obtained by sensing and analyzing the transmitted light.
In the prior art, for example, if biological feature detection is implemented by combining the biological feature detection function with an earphone, the entire dimension of the earphone is great, and wearing comfort is poor.